Glider with flexing wing



June 1965 J. H. ROBERTSON 3,187,460

GLIDER WITH FLEXING WING Filed Nov. 26, 1962 2 Sheets-Sheet l FIG-4.

INVENTOR. JA MES H. ROBERTSON my MGQJQ v A TTORA/EY June 8, 1965 J. H. ROBERTSON emnna WITH FLEXING mm 2 Sheets-Sheet 2 Filed Nov. 26. 1962 IN VENTOR. JAMES H. P0552750 A TTOEA/E Y United States Patent GLIDER WITH FLEXING WING James H. Robertson, Burbank, Calif, assignor to Gym Plastics Corp., Burbank, Calif., a corporation of California Filed Nov. 26, 1962, Ser. No. 239,951 7 Claims. (Cl. 4679) This invention relates to toy airplanes.

It is the principal object of my invention to provide a toy airplane which is capable of being easily projected to substantially greater heights than conventional toy airplanes now in use and which, after reaching such heights, is adapted to glide back to earth in the same manner as a conventional toy airplane.

It is an object of my invention to provide a toy airplane which is adapted to be projected to greater heights in a substantially straight upward path, due to alternation of the normal camber of the airplane wing, which acts to prevent the airplane from prematurely looping and terminating its upward flight as a conventional toy airplane would.

Another object of my invention is to provide a toy airplane of the type described in which the camber of the airplane wing returns to normal as the airplane approaches the end of its upward flight, so that the airplane will glide slowly back to earth in a normal manner.

It is a further object of my invention to provide a toy airplane in which these variations in the camber of the wing take place automatically and preferably because of the construction of the airplane wing at the time it is manufactured.

In essence, my invention contemplates a toy airplane having a pair of outwardly directed Wings. One of the wings is providedbetween its ends with a preferably transversely directed score line or other line of bending movement 'whereby during vertical flight of the airplane, the outer portion of the wing beyond the score line will be bent or deformed to reduce the camber of the wing and alter its flight characteristics in such a manner as to permit upward twisting flight of the airplane. As the airpl-ane reaches its highest point, the forces tending to bend or deform the outer portion of the wing are reduced or disappear and the end of the wing automatically returns to its normal position, thus returning the normal camber and flight characteristics of the wing so that the airplane will glide down in a conventional manner.

My invention also comprises such other objections, advantages and capabilities as will later more fully appear and which are inherently possessed by my invention.

While I have shown in the accompanying drawings a preferred embodiment of my invention, it should be understood that the same is susceptible of modification and change without departing from the spirit of my invention.

Referring to the drawings.

FIG. 1 is a top plan view of a toy airplane embodying my invention;

FIG. 2 is a side elevational view of the same;

FIG. 3 is an enlarged fragmentary sectional view taken on line 3-3 of FIG. 1, showing the score line;

FIG. 4 is a schematic view showing the flight path of the airplane;

FIG. 5 is a top plan view, similar to FIG. 1, showing the airplane in vertical flight with the outer wing section deformed to a ninety degree angle;

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FIG. 6 is a front elevational view of the airplane as in FIG. 5 with the direction of twisting of the airplane indicated by an arrow;

FIG. 7 is a sectional view taken on line 7-7 of FIG. 5, showing the deformation of the wing camber along the score line to a substantially straight line;

FIG. 8 is a sectional view taken on line 8-8 of FIG. 5, showing the normal camber of the wing.

A preferred embodiment which has been selected to illustrate my invention comprises a toy airplane 10 having a fuselage 11 and a pair of wings 12 and 13, which are directed outwardly in opposite directions from the fuselage 11. The fuselage 11, one of the wings 12 and the remainder of the toy airplane are constructed in a normal and conventional manner. The configuration of the airplane, including its fuselage and wings, may be varied as desired to simulate any type of airplane. The material used to construct the airplane is preferably light but rigid material such as polystyrene foam or balsa wood.

The novelty of my invention resides in the construction of the other wing 13 which is provided between the fuselage 11 and the outer end of the wing 13 with a transversely directed. score line 14 or other suitably formed line of bending movement, which may extend partially through the material forming the wing 13 to create a weakened line along which the wing 13 will tend to bend.

The score line 14 or other line or bending movement is preferably such, however, as not to completely destroy the strength of the wing 13. The configuration of the wing 13 ispreferably identical with that of the other wing 12 except when the airplane is projected into vertical flight. Both of the wings 12 and 13 are provided with a slight curvature or camber which acts to sustain the airplane in flight by providing a lifting force adjacent to both of the wings.

The toy airplane is adapted to be projected into directly vertical flight by an elastic band or other suitable launching or projecting means, not shown in drawings. As the airplane flies upwardly at a rapid rate of speed, the flow of air along the surfaces of both wings creates a lifting force, due to the camber of the wings. When the nose of the airplane is pointed straight up, the lifting force is directed at right angles to the vertical line of flight. This force normally acts to pull the airplane horizontally and cause it to loop.

With my invention, however, the score line 14 divides thewing 13 into an outer portion 15 and an inner portion 16. The outer portion 15 is free to move in response to this force and will accordingly bend or flex along the score line 14 to extend at an angle to the inner portion 16. This bending or flexing action may be anywhere from a slight angle of bending to as much as ninety degrees.

The bending of the outer portion 15 of the wing 13 substantially destroys the lifting force of the wing 13. The airplane will accordingly continue to inove upwardly and will rotate slowly about its longitudinal axis, due to the lifting action which is still exerted upon the other wing 12. The airplane will accordingly rotate in a clockwise direction when viewed from the top or front if the wing 13 is on the left of the port side and in the opmal position. The camber or curvature of the wing 13 acts to urge the outer portion of the wing 13 back to its normal position in alignment with the inner portion 16. This results from the fact that the deformation of the outer portion 15 of the wing 13 causes the portion of the wing 13 along the score line 14 to be deformed from its normally curved contour to a flatter or substantially straight line contour, as indicated in FIG. 7 of the drawings.

This action iscomparable to deforming a normally curved spring to a straight position. The wing 13 accordingly tends to return from the deformed contour shown in FIG. 7 of the drawings to its normal curved contour shown in FIG. 8 of the drawings.

As the airplane reaches or approaches the maximum point of its upward flight, the wing 13 will accordingly automatically revert to its normal position and the airplane will accordingly glide slowly back to the earth in the same manner as any conventional toy airplane, entirely uneffected by the score line 14.

While I have shown in the drawings and described herein a preferred embodiment of my invention in which the deformation or alteration of the wing camber and its return to normal take place automatically due to the resilient action of the Wing, it should also be understood that the same principles may be used in other embodiments in which either or both of the deformation or .alteration and return movements of the wing are either entirely controlled or assisted by otherresilient means or other suitable control means.

The material used to form the wing of my toy airplane should preferably be a material which is rigid but has a certain amount of resilience. One type of material which has been found to be particularly suitable is relatively thin polystyrene foam sheet plastic having a thickness of anywhere from to A.". Other plastics such as rigid vinyl, styrene, acetate and other similar plastics may be used in either sheet or molded form. If the outer portion of the wing is hinged, any material can be used and resilient means provided to return the outer portion of the wing to its normal position.

It should also be understood that the toy-airplane may have self-propelling means for use during its initial vertical and/or horizontal flights.

While the foregoing description refers to the initial flight of the airplane as being vertical, it is obvious that the actions described will also take place if the airplane is projected horizontally or-at any otherangle whatsoever, as long as care is taken to avoid contact between the airplane and the ground during its flight.

I claim:

1. In a toy airplane having a'pair of wings, one of said wings having means responsive to excessive lifting force exerted upon said wing during the projection of said airplane into rapid vertical flight to automatically deform the configuration of at least a portion of said wing and cause said airplane to rotate about its longitudinal axis instead of prematurely looping, said wing having means acting automatically upon the diminution of said lifting force to return said wing to its normal configuration and lifting action, to permit continued normal horizontal flight of said airplane thereafter.

2. In a toy airplane having a pair of wings, means carried by said airplane for substantiallydeforming the configuration of at least a portion of one of said wings automatically upon the projection of said airplane into rapid vertical flight, such deformation acting to substantially destroy the lifting action of said wing and to cause said airplane to twist about its longitudinal axis during said vertical flight instead of prematurely looping, and means carried by said airplane for automatically returning said deformed wing to its normal configuration upon the completion of said rapid vertical flight, to permit continued normal horizontal flight of said airplane thereafter.

3. In a toy airplane having a'pair of wings, means carried by said airplane for substantially deforming the configuration of at least a portion of one of said wings during the projection of said airplane into rapid vertical flight, such deformation acting to substantially destroy the lifting action of said wing to cause said airplane to twist about its longitudinal axis during said vertical flight instead of prematurely looping, and means carried by said airplane for returning said deformed portion of said wing to its normal configuration and lifting action upon the completion of said rapid vertical flight, to permit continued normal horizontal flight of said airplane thereafter.

4. A toy airplane comprising a fuselage and a pair of normally substantially straight wings extending outwardly in opposite directions therefrom, at least one of said wings being formed of thin somewhat resilient polystyrene foam material, said wing normally having a slightly convex curvature from front to back thereof, means extending substantially transversely across the entire width of said wing adjacent the midportion thereof forming a line of flexing movement dividing said wing into outer and inner portions so that said outer portion of said wing is responsive to excessive lifting force exerted upon said wing by the flow of air across said wing during the projection of said airplane into rapid vertical flight and said outer portion will automatically lift and flex into an angular position with respect to said inner portion, said flexing action deforming said wing along said score line from its normal curved contour to a substantially straight contour against the urging of said wing, the flexing. of said outer portion substantially destroying the lifting action of said wing to cause said airplane to rotate about its longitudinal axis instead of prematurely looping, said outer portion of said wing acting automatically due to the spring-like urging of said wing in returning to its normal curved contour upon the slowing of said airplane and the diminution of said lifting force to overcome said lifting force and flex back to its normal position in substantial alignment with said inner portion, to permit said airplane to continue in normal horizontal flight thereafter.

5. A toy airplane as described in claim 4, in which said means comprises a score line extending substantially transversely across said wing.

6. In a toy airplane having a pair of normally substantially straight wings, at least one of said wings being formed of somewhat resilient material, said wing normally having a slightly convex curvature from front to back thereof, means extending substantially transversely across saidwing forming a line of flexing movement dividing said Wing into outer and inner portions so that said outer portion of said wing is responsive to excessive lifting force exerted upon said wing upon the projection of said airplane into rapid vertical flight and said outer portion will automatically lift and flex into an angular position with respect to said inner portion, said flexing action deforming said wing along said score line from its normal curved contour to a substantially straight contour against the urging of said wing, the flexing of said outer portion substantially destroying the lifting action of said wing to cause said airplane to rotate about its longitudinal axis instead of prematurely looping, said outer portion of said wing acting automatically due to the spring-like urging of said wing in returning to its normal curved contour upon the slowing of said airplane and the diminution of said lifting force to overcomesaid lifting force and flex back to its normal position in substantial alignment with said inner portion, to permit said airplane to continue in normal horizontal flight thereafter.

7. In a toy airplane having a pair of normally substantially straight wings, at least one of said wings being formed of somewhat resilient material, said wing normally having a slightly convex curvature from front to back thereof, means extending substantially across said wing forming a line of flexing movement dividing said wing into outer and inner portions, so that said outer por tion of said wing is responsive to excessive lifting force exerted upon said wing by the flow of air across said Wing during rapid vertical flight of said airplane and said outer portion will automatically lift and flex into an angular position with respect to said inner portion, the flexing of said outer portion substantially destroying the lifting action of said wing to cause said airplane to rotate about its longitudinal axis instead of prematurely looping, and means carried by said airplane acting automatically upon the diminution of said lifting force to flex said outer portion of said wing back to its normal position in substantial alignment with said inner portion, to permit said airplane to continue in normal horizontal flight thereafter.

References Cited by the Examiner UNITED STATES PATENTS 3,063,191 11/62 Main 46--79 3,091,889 6/63 Zaic 46-79 OTHER REFERENCES Pelaspan Expandable Polystyrene, Dow Chemical Company, Catalog No. 171-90, February 1958, pg. 31,

10 Fig. 31 relied on.

I LOUIS R. PRINCE, Primary Examiner.

RICHARD C. PINKHAM, Examiner; 

1. IN A TOY AIRPLANE HAVING A PAIR OF WINGS, ONE OF SAID WINGS HAVING MEANS RESPONSIVE TO EXCESSIVE LIFTING FORCE EXERTED UPON SAID WING DURING THE PROJECTION OF SAID AIRPLANE INTO RAPID VERTICAL FLIGHT TO AUTOMATICALLY DEFORM THE CONFIGURATION OF AT LEAST A PORTION OF SAID WING AND CAUSE SAID AIRPLANE TO ROTATE ABOUT ITS LONGITUDINAL AXIS INSTEAD OF PREMATURELY LOOPING, SAID WING HAVING MEANS ACTING AUTOMATICALLY UPON THE DIMINUTION OF SAID LIFTING FORCE TO RETURN SAID WING TO ITS NORMAL CONFIGURATION AND LIFTING ACTION, TO PERMIT CONTINUED NORMAL HORIZONTAL FLIGHT OF SAID AIRPLANE THEREAFTER. 